Tubular lamp and socket housing juncture seal



May 16, 1961 E. M. CAFERRO 2,934,812

TUBULAR LAMP AND SOCKET HOUSING JUNCTURE SEAL Filed Oct. 25, 1956 2Sheets-Sheet 1 FIG-4 INVENTOR. EDWARD M. OAFERRO May 16, 1961 E. M.CAFERRO TUBULAR LAMP AND SOCKET HOUSING JUNCTURE SEAL 2 Sheets-Sheet 2Filed Oct. 23, 1956 INVENTOR. EDWARD" M. CAFERRO BY United States PatentTUBULAR LAMP AND SOCKET HOUSING JUNCTURE SEAL Edward M. Caferro,Spokane, Wash, assignor to Columbia Electric & Mfg, Spokane, Wash., acorporation of Washington Filed Oct. 23, 1956, Ser. No. 617,722

3 Claims. (Cl. 339-52) The present invention relates to electricalfixtures and in particular to a seal for the juncture of tubular lampsand socket housings.

Outdoor lighting systems employing tubular lamps such as are commonlytermed fluorescent lights, are becoming increasingly popular andconsiderable effort is being expended to improve the facilities for thisfield of use. Obviously, any electrical fixture to be employed outsidemust be provided with means for protection against inclement weather.

Housings for the socket connections have been made comparativelyweatherproof and shields have been provided to protect the lamp andtheir junctures with the housings against normal precipitation. However,under extreme weather conditions, including rain and snow driven by highwinds and rapid temperature changes where moisture in the air iscondensed on the metal parts, it is required that an additional seal'beprovided to protect the opening at the juncture of the tubular lamp andthe socket housing.

The sockets in this type of lighting conventionally have one fixedsocket at one end and a spring-loaded socket at the opposed end and thelamps are applied by forcing the end inwardly to compress the spring inthe one socket and then allowing its return rectilinear movement so thatthe prong or prongs of the opposed end will be disposed in the opposedfixed socket.

Heretofore an attempt has been made to seal the junctures between thehousings supporting the sockets and the lamps by employing a straightcylindrical resilient sleeve which has a slightly smaller internaldimension than the external dimensions of the cylindrical socket housingprojection and the external circumference of the tubular lamp. This hasnot proven to be satisfactory, however, because of the difiiculty inapplying the sleeve over the lamp and the cylindrical projection of thesocket housing, and in addition it has been found that the naturalresiliency of the conventional cylindrical sleeve often times opposesthe bias of the socket spring sufficiently to preclude the contact prongor prongs from properly mating with their companion socket members atthe opposed ends.

The present invention seeks to overcome these undesirable features andprovides a sealing device which is easily applied to the socket housing,readily receives the tubular lamp, and does not greatly resist the biasof the conventional spring loaded socket thus resulting in properelectrical connection of the prongs and their companion sockets.

Other objects and advantages of the invention will become apparent toone during a reading of the following specification which refers to thedrawings in which a preferred embodiment of the present invention isdisclosed.

In the accompanying drawings, like numerals are employed to designatelike parts in each of the several views wherein:

Figure l is a perspectve view of two spaced housings having tubularlamps associated therewith and their junctures sealed by the sealsconstituting the subject matter of the present invention;

Figure 2 is an enlarged vertical view partially in side elevation incross section as at the plane indicated by line 22 of Figure 1;

Figure 3 is an end view of the weather tight sleeve viewed from thesmall end thereof; and

Figure 4 is a vertical axial cross section on the plane indicated byline 44 of Figure 3.

Having reference now in a greater degree of particularity to thestructure as revealed in the several views, I have shown socket housings10 having cylindrical extensions 12 disposed in axial alignment andopposing each other. The shields or hoods =14, indicated by the dot anddash lines, are secured to and carried by said extensions 12. At theirouter ends the cylindrical extensions 12 are each provided with acircumferentially extending groove 16 and the cylindrical extensions 12are adapted to receive the electrical sockets 18.

Since the sockets 18 are of conventional and well known constructiontheir details are not taught to be required for a proper understandingof the present invention and therefore are omitted from thisspecification with the exception of stating that at least one of eachpair of sockets is depressible to admit a lamp 24 therebetween.

The socket housings 10 are provided with means for connecting conduit'20 through which conventional wiring '22 extends to electricallyconnect the sockets 18.

The tubular lamps 24 are of conventional construction and have single orplural prongs (not shown) on each end. The prongs are adapted toco-operate with the sockets 18, and electrically connect the lamps forillumination by the electricity.

The lamps 24 have junctures with the socket housings 10 wherein thereare minute spaces between the lamp and the socket as seen at 26, andalso between the lamp socket and the socket housing as seen at 28.

To provide a weather tight seal over this juncture I have devised theseal constituting the subject matter of this application. The seal 30 ismade from an impervious resilient material, for example neoprene rubber.In actual practice the material found best suited for the purpose, isneoprene compound No. 337ZF of the Minnesota Rubber and Gas Company,45-50 durometer.

As will be seen in the several views the Weather tight seal comprises ahollow progressively divergent annular sleeve-like body 32, having acircumferentially reduced end 34 and a circumferentially enlarged end36. An internal annular bead 38 is provided on the inner periphery ofthe body 32 at the reduced end thereof, and an annular external groove40 is formed in the outer peripheral face of the body 32 adjacent to thereduced end 34 thereof, and intermediate the axial width of the bead 38.The groove 40 is provided to receive a split retainer ring 42 which ismade of a carbon spring steel and has a normally relaxed internalcircumference slightly less than the circumference of the bottom of thegroove 40, so that the ring when positioned in the groove, will clampthe bead 38 into the groove 16 of the housing extension 12, andhermetically seal the bead to the groove 16.

The body is provided externally with tri-radiate ribs 44 which mergeinto the circumferential dimension of the body at the enlarged end 36,and which extend toward the reduced end a distance more than midway theaxial length of the sleeve with their outer defining edges in parallelrelationship to each other, thus forming ribs which increase in radialsize progressively toward the reduced end of the body 32 and terminatespaced from the reduced end thereof. These ribs are provided to stiffenthe body and prevent the resilient flexible body from folding back uponitself when the lamp end is inserted therein. V

The enlarged end of the sleeve body 32 has a diameter somewhat enlargedover the external circumference of the lamp body 24, but is providedwith an inwardly extending radially disposed flange 46 having an arcuateinner edge face 48 which defines an annular aperture somewhat smallerthan the external circumference of the lamp with which it is to seal andconstituting means for sealing with a lamp irrespective of its obtuse oracute angular position relative to the sleeve-like body 32. The arcuateinner edge face 48 is convex when viewed in cross sectionalconfiguration as seen in Figure 4. This provides for angular positioningof the flange 46, with respect to the cylindrical face of the lamp 24and still maintains an acceptable seal therebetween. The two primarypositions of the flanges are shown in Figure 2 on the weather tight sealdisclosed on the intermediate weather type seal and an end seal 30.

It will also be noted that the flange 46 is disposed inwardly spacedfrom the enlarged end 36 a slight distance to provide an angular endface at 50 disposed between the enlarged end 36 and the flange 46. Thisprovides area for finger holds for easy manipulation of the seal when itis found to be necessary.

In actual use the weather tight seal 30 is applied to the socket housingextension 12, as previously defined, by placing the head 38 in thegroove 16 and then applying the clamping ring 42 in the groove 40 toseal the bead 38 in said groove 16.

As seen in Figures 1 and 2, a lamp 24 is inserted into the socket 18with the leftward end being admitted first and the lamp end is forcedthrough the aperture defined by the flange 46 to a seating engagementwith the companion socket 18 which is the spring loaded socket. The lampis then forced inwardly to compress the spring bias of the socket andthe flange 46 is by frictional engagement with the lamp 24, shiftedinwardly to an angular position relative to the periphery of the lamp,whereupon the opposed end of the lamp is aligned with the weather tightseal 30. This is accomplished by compressing the seal with the fingersuntil the prongs and the lamp end can be put into alignment with theopposed seal 30. Then the lamp is shifted in the opposite direction, orrightwardly, until the opposed end of the lamp is in electrical contactwith the rightward socket 18 at which time the leftward flange 46assumes a position shown by the intermediate seal 30 and the rightwardflange 46 assumes a position shown by the end seal 30. Since theinternal annular opening defined by the flanges 46 is somewhat smallerthan the actual circumference of the lamp 24, the resiliency of theflanges 46 adequately eifects sealing with the lamps to prevent passageof moisture into the socket housings and sockets.

The bias of the flanges 46 to seek their normal radial plane is notsuflicient to interfere with the spring bias of the conventional socketsand therefore the electrical contact is constant and insured.

Having thus described my invention I claim the followmg:

1. As an article of manufacture, a weather tight seal for tubular lampsand socket housing junctures comprising a hollow progressively divergentannular sleeve-like body; an internal bead at the reduced end of saidbody for hermetically sealing with a socket housing; an inwardlyprojecting resilient annular flange at the enlarged end of said body,movable between an obtuse and an acute angle with respect to the bodyand defining an annular aperture smaller than the external circumferenceof the lamp with which it is to seal; the internal defining edge of saidflange being convex in cross sectional configuration, axially extendingreinforcing ribs merging with the body at its enlarged end and extendingaxially toward the opposed ends substantially more than one-half itslength and being formed integrally therewith.

2. In combination with a socket housing having a cylindrical extensioncontaining a lamp socket and a tubular lamp operably connectedtherewith, said cylindrical extension having an annular groove therein,of a weather tight seal comprising a hollow progressively divergentannular sleeve-like body; an internal bead at the reduced end of saidbody disposed in said annular groove; said body having an annular grooveand disposed axially intermediate the width of said bead; a retainerring disposed in said last named groove and biased to hermetically sealsaid head in said first named groove; an inwardly projecting resilientflange at the enlarged end of said body and defining an annular apertureinitially smaller than the external circumference of the lamp encircledthereby and sealingly engaged therewith; the internal defining edge ofsaid flange being convex in cross sectional configuration to effectsealing at different angular relationships thereto, and t'ri-radiateaxially extending reinforcing ribs for said body.

3. As an article of manufacture a weather seal for tubular lamps andsocket housing junctures comprising, a hollow progressively divergentsleeve-like resilient body having at its reduced end means for sealingengagement with a socket housing; an inwardly projecting flange at theenlarged end of said body and defining an aperture commensurate in shapebut smaller in size than the external configuration of the lamp withwhich it is to seal; and integral axially extending reinforcing ribsmerging with the body at its enlarged end and extending axially towardthe opposed end more than one-half its length.

References Cited in the file of this patent UNITED STATES PATENTS1,745,345 Anderson Feb. 4, 1930 2,100,009 Hardy Nov. 23, 1937 2,119,452Woodhead May 31, 1938 2,333,266 Miller Nov. 2, 1943 2,364,194 CortnerDec. 5, 1944 2,732,530 Dahlhaus et a1. Jan. 24, 1956 2,774,947 FrenschDec. 18, 1956

